Climate averages 1991–2020

San Francisco weather
in April.

A mild, fairly dry month: the 7th warmest and the 7th driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 17.0°C Daytime mean, April
Average low 8.8°C Night-time mean, April
Rainfall 37 mm 5 days with ≥1 mm
Daylight 13 h Sunrise to sunset, per day
Every month in San Francisco · average highYear overview

April is a mild month in San Francisco: daytime highs average 17.0°C and nights cool to about 8.8°C. By daytime temperature it is the 7th warmest of the 12 months.

Expect about 37 mm of rain on roughly 5 days, which makes April a fairly dry month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 09 min on an average April day.

The nearest other city in this atlas is Daly City (9 km away). In April its highs average 15.1°C, 2.0°C cooler than San Francisco, with 37 mm of rain.

Among the 498 cities listed in the United States, San Francisco ranks joint 315th of 498 for the warmest April highs and joint 116th of 498 for the driest April (rainfall, lowest first). The mean April high of those 498 cities is 19.4°C; San Francisco is 2.3°C cooler than that mean.

From April to May, average highs rise by 1.8°C to 18.8°C, and monthly rainfall falls from 37 mm to 18 mm.

The annual picture

April in context

30-year average
Average highAverage low°C
Average daily high and low temperatures by month The same values are available in the monthly table below. Lines show mean daily maxima and minima, not a forecast interval. 0510152025 JanFebMarAprMayJunJulAugSepOctNovDec

Monthly rainfall

Average total · mm
Average monthly rainfall totalsEach bar is a mean monthly total over 1991–2020. Full numbers are in the table. JanFebMarAprMayJunJulAugSepOctNovDec 1500

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

San Francisco climate table

1991–2020
Monthly climate averages for San Francisco, 1991–2020
MonthAverage highHigh / lowAverage lowRainfall mm/monthRain days ≥1 mm/dayDaylight hours/dayDay­light h/day
January 13.6°C6.1°C6.1°C10910.19.910 h
February 14.6°C7.0°C7.0°C1139.510.811 h
March 15.7°C8.1°C8.1°C819.311.912 h
April, selected 17.0°C8.8°C8.8°C375.013.113 h
May 18.8°C10.4°C10.4°C182.814.214 h
June 21.0°C11.7°C11.7°C4.30.814.715 h
July 21.5°C12.6°C12.6°C0.30.114.515 h
August 22.1°C13.2°C13.2°C0.70.113.614 h
September 22.7°C13.0°C13.0°C1.50.412.512 h
October 21.0°C11.8°C11.8°C243.111.311 h
November 16.6°C8.7°C8.7°C566.110.210 h
December 13.5°C6.3°C6.3°C10810.19.610 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

April in nearby cities

Distance from San Francisco

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for San Francisco) is explained once on the San Francisco year overview and on the Sources, method and limits page.

Daly City lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.